INVESTIGATION OF VHI AFFECTED BY THE DENSITY OF MECHANORECEPTIVE UNITS FOR VIRTUAL SENSATION

摘要

The velvet hand illusion (VHI) is an innovative tactile illusion that enables a human toperceive a velvety sensation by gently rubbing the hands on both sides of wire mesh string through aframe. In order to enhance tactile displays presentation ability, VHI’s mechanism is applied through aseries of psychophysical experiments. In this paper, we have investigated the effects of several physicalparameters on intensity variation of VHI in subjects’ fingers and fingertips, such as wire distance Dand a dimensionless ratio of wire stroke r to wire distance r/D in passive touch based on psychophysicalexperiment. We obtain D = 45 mm and r/D ≈ 1 as optimum values for VHI intensity for wire distance and the ratio, respectively. Furthermore, as the result of comparison between the present result and theprevious result for palm, we conclude that a combination of mechanoreceptive afferent units, SAI, SAIIand FAI, are involved in VHI. VHI mechanism is induced when movement of wires is accepted throughFAI under constant compressive stimulus for SAI and no shearing force for SAII. This result indicatesthat VHI can be generated by normal pin matrix type tactile displays because no stimulation of SAII isrequired.